Fluorescent substance



' Patented Jan. 21 1936 FLUORESCENT SUBSTANCE UNITED STATES Hans Rabe,

many, assignor to I. G.

Ludwigshafen-on-the-Rliine, Ger- Farbenindustrie Aktien- )Serial No. 700,080.

The present invention relates to substances which are soluble in hydrocarbon oils and produce fluorescence therein, and to aprocess of malging such substances; ii It is of aromatic hydrocarbons containing more than one nucleus substances are obtained under appropriateconditions of temperature and in the .the greater part of them is precipitated again f after allowing the solution to stand for some time and that in many cases opalescence. These products furthermore are not soluble in benzines but are precipitated by them.

It has been suggested elsewhere to produce substances producing fluorescence, which are readily soluble in hydrocarbon oils (by which expression I understand heavy oils or middle oils or lubrioating oils or liquid motor fuels, such as benzines, orother liquid hydrocarbon fractionswhether they may be'of naphthenic or paraflinic base), even at low temperatures, by subjecting;

oleflnes of purely aliphatic constitution which are liquid at; ordinary temperature or halogenatedparaffin wax hydrocarbons to condensation with polynuclear organic substances in which none oi! the nucleiis saturated with hydrogen, at an elevated temperature, in the presence of condens- 5 ing catalysts or the Friedel Crafts type, in particular aluminium chloride. Those, of the aforesaid polynuclear substances are of particular advantage which. are devoid of substituents.

such substances may be mentioned unsubstituted polynuclear aromatic hydrocarbons, such ,as

naphthalene or anthracene or' phenanthrene, or polynuclear heterocyclic compounds, such as carbazole. As oleflnes suitable as initial materials for in the .vapor such as hard or soft paraffin wax, petrolatum, or

oils entirely or mainly consisting of parafiinic hydrocarbons and also normally liquid oleflnes obtained by the dehydration of higher aliphatic alcohols, preferably such as contain at least 6' already knownv that by the polymerization they give only a slightthis conversion may be mentioned the liquidproducts obtained by .the cracking, preferably phase, of parafiinic hydrocarbons,

In Germany December 2,

' 7 Claims. (01. 260-163) and 200 C., or another oil boiling at the same or higher temperatures, and externally cooled simultaneously. The amount of polynuclear aromatic substances should be greater than 20 er cent of the amount of oleflne employed, but is advantageously not greater than from to per cent of the said amount 01 ,oleflnes since a surplus does not take part in the reaction, but acts only as a diluent and would have to be distilled from the resulting condensation product. The intensity of the fluorescence caused by a certain amount of the condensation product is greater, the greater the amount of aluminium chloride employed. .Preferably from 20 to 50 per cent of aluminium chloride with reference to 15 the amount of the initial olefines to be condensed are employed, though, larger amounts of aluminium chloride may be used. The products obtained according to the present invention ordi 20 narily have a mean molecular weight oi. between 600 and 800. The substances producing fluorescence thus obtained are thickly liquid, viscous products which at ordinary temperature may be dissolved 2 in hydrocarbon oils of naphthenic or paraflin base, such as in lubricating oils or in benzine. j No precipitation or resiniflcation occurs in the oils mixed with the said substances. The oils containing these substances are entirely clear in 30 transmitted light. An addition oi. from 0.1 'to' 0.2 per cent is suflicient for imparting to the oil a red color in transmitted light and a green color in incidentlighta The said products, however, when added to hy- 35 .drocarbon oils and especially lubricating oils, sometimes have the disadvantage that they pro- ;duce a green fluorescence having a bluish shade which is undesirable and which fluorescence often has'not sufflcient stability to light. j I have now found that this objection is avoided by employing for'the condensation not only condensing agents of the Friedel-Crafts type, in particular aluminium chloride, butj'al'so halides of metals of the 1st and 2nd groups of the periodic 45 system, as for example NaCl, NaBn-KCLGuCle, I-IgClz and CaClz, which salts do not catalyze the Friedel- Crafts reaction, .but which diminish the \action of the condensing catalyst. The method of workingis the same as when usingthe catalysts wlthouttheadditiohs. The products chtained, when added to anoii ior example in an 3 amount of from 0.2 to 1.0 per cent, imparta fluois not restricted to m tion "mixture has attained a temperature or zeam ze 1 whet: claim le': -i'

1. The process of producing a substance giv- 1 kilogram oi" naphthalene is condensed with V4 kilograms oftm 01 em e in ction, boning between ing rise to fluorescence when dissolved in a hy o drocarbon oil which comprises condensing a sub- 50 and, 250 C. under atmospheric pressure and stance selectd from the group consisting M 5 obtainedby splitting sort parafiin' wax at a temliquid defines of purelyanphatic nature and perature of 520 0., in the presence of 1.6 kilograms or aluminium chloride and 0.2 kilogram of halogenated paramn wax hydrocarbons with a I pblynuclear aromatic hydrocarbon in which sodmm chloride while sturmg' After the 'none of the nuclei is saturated with hydrogen, 150 0 the whole is kept at thistemperature for by 'f saidfubstances with a g g an hour. It is then allowed to cool and stirred fiz fi gfi gBFgZJififl g g g 2 with water and the sludge is separatediog' The ence of a halide of a metal selected from the ction product is distilled in vacuo at 2. millima o 1st and 2nd groups of the periodic system which ffggz i fi i g fizgfiig g gg g :':f:% halide does not 'catalyze the Frledel Crafts re- 15 residue 01' 4.6-kilo ams is a aste solublein on action 7 and benzine. An i ddition of atom 0.1 to 0.2 r i-$ gg g f g fgggg zgg f cent thereof to a'yellow colored oil imparts th 'i\ g p 1 gg ggg ggg ggfii i g g gi g; 3'.;The process oi'producing a substance Igiv- 20 abbut from t6 c ing rise tofluorescence when dissolved in a bytirocarbon oil which comprises condensing a sub- Bump}: z stance selected from the group consisting of liquid oleflnesof purely aliphatic nature and v 2 kilograms of a chlorinated soft paraflin wax' halogenated, paramn wax hydrocarbonsk with 25 having a chlorinmcontent of 18 per cent are disna hthaleneb Contact said substances solved in 1 kilogram Of 8 oil having a boilt t of ie i g tt a p at a mg mint mm perature between about 70 and about 250 0. in

naphthalene and a mixture of m the presence-oi a halide of a metal selected from minium chloride and 0.1 kilogram of sodium chloride then being added the solution while stirring. The whole is wor ed as in Example ,1. A Crafts, random paste is obtained in almost quantitative yield The process of pmdudng a substance 81% which whm aged to lubricating imparts a ing rise to fluorescence when dissolved in a hy-;

.which halide does not catalyze the Friedel tllel'eto green Rum in reflected drocarbon oil which comprises condensing a sub-.

fight a red cobra-on in MM fight stance selectedfrom e group consisting of t E aimpmveasemtng 9? by from liquidv oleflnes, of p aliphatic nature and. to 3 halogenated paraflin wax hydrocarbons witha the 1st and 2nd groups of the periodic system 80' 3 polynuclear aromatic hydrocarbon in which- 1 Q a V I none of the nuclei is saturated with hydrogen &0

A product having the same properties asthose I described in Examples 1 and 2 is obtained by by aontacflns said substanqes w m g condensing of a product chloride at a between about boiling between aha 2505a) (at 700 mimmeand about 250 C. in the presence of a halide of 4 ters) derived from crude paraflin wax, for half ametal selected m the s Zndgroups lene, 0.5 kilogram of anthracene, 0.5 kilogramof the-Frieda m m 'c'arbazole and a mixture of 1.2 kilograms of alu- Pmcess. 'P 8 Substance miniumchlcride, 0.05kilogramo1'sodiumchloride, i to fluorescence n i v d in a y- O3 kilogram of potassium bromide i m drocarbonoilwhich comprisescondensing a sub- 6 turefi of 'oleflnes obtained by the dehydration 01- not catalyze the medal Crafts 75 point by about from 5 to 8 C.

gram of cuprous chloride, the reaction product selected group consisting liquid 50 be g worked upas describedinthe said examples. oleflnes or pu aliphatic nature -h The flnalproduct also improves the coloration Rented Pmmn wax hydrocarbms i a l and lowers the setting point of lubricating ous" u aromatic hydrocarbon in which none bi? fromI5to 8 C.- I v the nuclei is saturated with hydrogen, by con- 5 acting said substances with a catalyst oi. the

I Example 4 Friedel Crafts type at a temperature between about 125 and about 200 C. in the resence of a kilograms of n al are W halide of a metal selected from the lst and 2nd t 100 C. while stirring with 4 kilograms of a. mixgroups t periodic system which na d hig er alcohols the condensationbeing effected 6 p I um 00 y ocessof roduc asubstance vingrise Wlth' kilogram? s aluminium 9 9 to fluorescence when d issolved inhyfil roc'arbon The i n product is stirred with water .oil which comprises condensingapurely aliphatic separated from sludge by' filtration, dried, subf e m f floflxboflj -betwe 5;? and 5 9 an hour at 165 C. withl kilogram of naphthathe Permdic system which halide 1165 1117 45 jected 'to an after treatment 'with a mixture c. with a polynuclear aromatic hy ocarbon in 55 a or 0.1 kilogram. of al mini m chloride and which none of the nuclei is satura with hy- 0.05 kilogramv of mercury chloride at C. drogen by contacting said substances with alu- 1 and again treated with water. After drying ininum chloride at a temperature between about the reactionproduct is distilled in a vacuum 70 and 250 C. in the presence of sodium L 70 of. 1 millimeter (mercury gauge). The residue chloride.

remaining above 200 C. constitutes a paste which '7. The process according to the preceding .whenadded to an oil in an amount 01' 0.5 per claim in which the polynuclear aromatic hydrocent imparts thereto a yellow-green fluorescence carbon is naphthalene and the condensation temwith redtransparency-and also lowers the setting peratureis about C.

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